Tension mechanism for looms.



E. E. SIBLEY TENSION MECHANISM FOR LOOMS.

AIPLIOATIOH FILED JULY'IB, 1910.

Patented Apr. 30, 1912.

2 SHEETS-SHEET 1.

UMBIA PLANOORAPH C0..WI\SH NGTON D c B. E. SIBLEY.

TENSION MECHANISM FOR LOOMS.

APPLIOATIONIILED JULY 16, 1910.

Patented Apr. 30, 1912.

2 SHEETS-SHEET 2.

SIBLEY, OF CHELSEA, MASSACHUSETTS.

EDWIN E.

TENSION MECHANISM FOR LOOMS.

Specification of Letters Patent.

1,024,528. Patented Apr. 30, 1912.

Application filed July 16, 1910. Serial No. 572,276.

To all whom "it may concern:

Be it known that I, EDWIN E. SIBLEY, of Chelsea, in the county ofSuffolk and State of Massachusetts, have invented certain new and usefulImprovements in Tension Mechanism for Looms, of which the following is aspecification.

This invention which is intended chiefly for looms for weaving elasticfabrics, although applicable for other purposes, has for its object toprovide simple and effective means for maintaining a uniform and, ifdesired, a regulable tension on flexible material such as threads, orstrands, forming parts of a woven fabric, or previously woven sheets orribbons, which are drawn from a source of supply for any purposerequiring a uniform tension on the material while it is passing from thesource of supply to a point where it is accumulated as a finishedproduct, or otherwise.

To these ends the invention consists in a loom having a tensionmechanism substantially as hereinafter described and claimed.

Of the accompanying drawings, which represent my invention embodied in atension device for elastic fabric looms,-Figure 1 represents a sideelevation of one form of tension mechanism embodying my invention, Fig.2 represents a top plan view of the same, Fig. 3 represents a frontelevation, Fig. 4 represents a section on line 44 of Fig. 3, Fig. 5represents a section on line 5-5 of Fig. 3, Fig. 6 represents a sideelevation of another form of tension mechanism embodying my invention,Fig. 7 represents a rear elevation of the same, Fig. 8 represents asection on line 8-8 of Fig. 6, Fig. 9 represents a perspective view ofthe strand guide shown in Fig. 7 and Fig. 10 represents a diagrammaticview showing the course of the strand engaged with the tension pulley,shown in Figs. 6, 7 and 8'.

Referring to the embodiment of the invention shown by Fi s. 1 to 5inclusive, (1, a represent a pair of brackets or hangers attached to abeam 1) forming a part of the frame of a loom, the bases of said hangersbeing formed to bear on and be attached to the beam. The outer ends ofthe hangers are provided with open bearings a, in which are journaledtrunnions or shaft ends 0, o aiiixed to and projecting from oppositesides of a pulley a, the periphery of which constitutes a movablesupport for elastic warp threads or strands d, said supports beinginterposed between a source of supply of said threads and the usualweaving and take-up mechanism of an elastic fabric or other loom. I- donot show the said weaving and take-up mechanism, this being well knownand comprising the usual heddles, lay, cloth beam and other componentparts.

In the embodiment of my invention now under consideration the warpthreads are stored in a holder d from which they pass as hereinafterdescribed to the periphery o the pulley 0.

6 represents a pressure roll having shaft ends or trunnions e which restupon and are in rolling contact with guides f, which are supported bythe hangers a and are inclined downwardly from the bases of the hangerstoward the bearings a so that the roll 6 is caused by gravitation tomove toward the pulley 0. The hangers a are here shown as of the formusually employed to support the warp spools or beams of an elasticfabric loom, the pulley 0 taking the place of the said spool or beam.The guides f are shown as separate pieces having studs f bearingprovided on warp beam hangers to support the weightedtension or-brakecords hereinafter referred to.

The warp threads d pass through fixed guides 9 arranged to present orguide said threads to the rear side of the pressure roll 6, the threadspassing over said roll between the latter and the pulley 0, under thepulley, and over the upper portion thereof, and from the pulley acrossthe frame beam 12 to the weaving mechanism, as shown by Fig. 4:.

The threads are nipped or pinched between the roll and pulley andportions of the threads are held in tractional engagement with theperipheries of the roll and pulley. Means are provided for yieldinglyresisting the rotation of the roll and pulley so that the strain exertedon the warp threads by the take-up mechanism is resisted sufliciently toset up the desired tension in the threads and properly stretch the same.The means here shown for this purpose include cords h attached at oneend to the uprights a and passing around the end portions of the pulley,weights h attached to the free ends of said cords and holding the latterin frictional engagement with the pulley, cords 71 attached at i to theloom frame and passing partly around the end portions of the roll 0, andweights 7? attached on opposite sides of the uprights a usually to thefree ends of the cords 2' and holding said cords in frictionalengagement with the pressure roll. The portions of the pulley andpressure roll engaged by the said cords are preferably grooved toprevent dis placement of the cords.

In an elastic fabric loom the resistance to the rotation of the roll andpulley in connection with the strain exerted on the elastic warp threadsby the take-up causes an intermittent rotation of the pulley, the latterremaining at restuntil the threads have been sufliciently stretched, andthen being rotated by the threads, the rotation of the pulley beingstep-by-step or intermittent. The pressure roll is preferably weighted,to increase its pressure on the threads, by cords j depending from thetrunnions (2 and weights j attached to the free ends of said cords.

Means are provided for holding the pressure roll in an inoperativeposition away from the pulley to release the warp threads and permittheir contraction. To this end the guides f are provided with notches fadapted to engage the trunnions 6 when the roll is moved back from thepulley, and thus hold the roll in a retracted position.

Referring to the embodiment of my invention shown by Figs. 6 to 10inclusive, 12 represents a pulley having a cylindrical periphery androtatably mounted 011 a suitable supporting frame or stand, which may inelude two side members 13, 13, connected at their upper portions by atransverse stud or pin 1%, rigidly secured so that it does not rotate,the pulley being rotatable on said stud. In this case the means foryieldingly resisting the rotation of the pulley comprise two collars 15,16, one having a flange 17, bearing on one side of the web of thepulley, and the other having a flange 18, hearing on the opposite sideof said web, the said flanges being in frictional contact with the web.The collar 15 is rigidly secured to the stud 14 by a pin 19. The collar16 has a sliding engagement with the stud 14; so that it is preventedfrom rotating and ismovable toward and from the collar 15, the collar 16being provided with a key 20 which is movable in a groove 21 in the stud141-. The said stud has a screw-threade ;l portion with which is engageda nut 22 bearing on the collar 16. The flanges l7 and 18, which areprevented from rotating by the means de scribed, by their frictionalcontact with the sides of the pulley web, offer a yielding re sistanceto the rotation of the pulley, the dothe periphery of the pulley 12, ashere shown, include an idle pressure roll 24: and a beam or spool 25,each of which is adapted to rotate loosely and is pressed yieldinglytoward the periphery of the pulley 12, the relative arrangement of thepulley, the roll and the spool, being such that the roll guides thestrands 23 from the spool to the periphery of the pulley and pressesthem against said periphery, the spool or the aecumulation of materialthereon, being pressed yieldingly against the portion of the strandswhich pass from the roll partly around the periphery of the pulley. Thearrangement of the pulley relatively to the mechanism of the loom issuch that the portions of the strands which pass from the pulley to theloom are in relatively close proximity to the roll 24:, so that thestrands are in contact with a considerable part of the periphery of thepulley, as indicated in Fig. 5. The roll 24 is journaled in a swingingsupport composed of side members 26, mounted to swing on a pivot bar orstud 27, supported by the stand. Springs 28 connecting the swinging sidemembers 26 with the stand draw the roll 24 yieldingly toward the pulley12.

The spool 25 is removably journaled in open bearings formed in the outerends of a swinging support composed of side members 29, which are alsomounted to swing on the pivot stud 27, and are acted on by springs 30which yieldingly draw the spool toward the periphery of the pulley. Thespool is provided with heads or flanges 31, which overlap the sides ofthe pulley, as indicated in Figs. 6 and 7. The swinging frame whichsupports the roll 24 is provided with guides 32, between which thestrands pass on their way to the roll 24, said guides preventing lateraldisplacement of the strands.

33, 33, represent fixed guides attached to the upper portion of thestand and occupying such relation to the pulley that they prevent thestrands from being displaced laterally from the upper side of theperiphery of the pulley.

It will be seen that a warp thread or strand 23 moved in the directionindicated by the arrows in Fig. 10, by the take-up mechanism of theloom, or other suitable means, is caused by its tractional engagementwith the pulley 12, to rotate said pulley. It will also be seen that thedescribed yielding resistance to the rotation gree of resistance beingdetermined by the of the pulley is imparted through the pulleyadjustment of the nut 22. If desired, the to the strand, so that theportion of the strand between the pulley 12 and the takeup mechanism iskept at a uniform degree of tension. The uniformity of the tension isdue to the fact that the strand is so pinched between the two movablesurfaces provided by the roll and pulley that it can flanges 17 and 18,or one of them, may be provided with a facing of felt, or othercompressible material, bearing on the web of the pulley.

The means for holding warp threads or strands 23 in tractionalengagement with not slip, and the further fact that the pulley supportsonly the limited extent of the strand that is in contact with itsperiphery and does not constitute a supply spool on which anaccumulation of the strand is wound. In tension mechanisms of thischaracter in which a tension device is applied directly to the supplyspool, which decreases in diameter as the material is removed from it,there is a corresponding variation in the tension on the strand passingfrom the spool to the take-up mechanism, the tension increasing as thediameter of the spool decreases. In my improved mechanism the tensionpulley 12 is entirely independent of, and unafli'ected by the diameterof the accumulation of material on the supply spool, consequently, thestrand tractionally engaged with the pulley, is always under the sametension, while the frictional device remains at a given adjustment. Thetension may be regulated to any extent desired by varying the weight hin the first described embodiment of the invention, or by regulating thepressure of the flanges 17 and 18 on the sides of the pulley in the lastdescribed embodiment.

Either of the described forms of tension mechanism is particularlyuseful and valuable in elastic fabric looms, because it enables anabsolutely uniform tension to be applied to the elastic rubber strands.Owing to the present hlgh cost of rubber, variations in the tension ofthe threads are liable to result in loss to the manufacturer, in casethe tension becomes less than the predetermined degree, so that therubber is not properly stretched when incorporated into the fabric.

My invention is not limited to the details of construction here shown,and the same may be modified in various respects, without departing fromthe spirit of the invention.

An important feature of my invention, so far as the same relates to anelastic fabric loom, is the provision of means for exerting a positivepinch, bite or grip on the elastic warp threads, such as is caused bythe yielding pressure of the roll 6 on the pulley a, said pinch or gripholding the warp threads at a point between the supply and the take-upuntil a predetermined stretch or tension is imparted to the portions ofthe threads between the point where they are gripped and the take-up,which pinch or grip will then yield, due to the brake mechanismpermitting a slip of the pulley, and so permit the threads to be movedwith the gripping surfaces until the tension is sufliciently reduced toenable the brake to cause the gripping surfaces to again locally arrestthe threads, whereupon the threads are again stretched as before, untilthe gripping pressure is overcome, the result being the maintenance of apractically uniform tension on the threads, because the gripping andrelease of the threads follow each other in such rapid succession thatthere is no material fluctuation or variation in the stretch or tensionof the threads between the gripping point and the take-up.

I claim 1. In a loom, a let-off for elastic warps comprising incombination a warp supply means, a support, a warp roller journaled inthe support, an auxiliary roller, means to cause said auxiliary rollerto yieldingly bear upon said warp roller, means for braking saidrollers, the warps passing from the supply means between the two rollersand over a suflicient extent of the periphery of the warp roller tocause said warp roller to be rotated by the friction and pull ofv thewarps, said warps passing thence to the heddles, said auxiliary rollerbeing adapted to yieldingly pinch the warps against the warp rollerapproximately at the point where they take on to said roller, said warpsbeing thereby left free to creep over the surface of said warp rollerbeyond said pinch point.

2. In a loom, a let-off for elastic warps comprising in combination awarp supply means, a support, a warp roller journaled 5 in the support,an auxiliary roller, means to cause said auxiliary rollerto yieldinglybear upon said warp roller, means for braking said rollers, the warpspassing from the supply means over the auxiliary roller about thesubstantially entire periphery of the warp roller and thence to theheddles,- said auxiliary roller being adapted to yieldingly pinch thewarps against the warp roller at the point where they take onto saidwvarp roller, said warps being thereby left free to creep over thesurface of said warp roller beyond said pinch point.

3. A tension mechanism for looms, comprising hangers having basesaffixed to the frame of the loom, pulley bearings at their outerportions and guides inclined downwardly from the said bases toward thebearings, a pulley journaled in said bearings and free to be rotated bythe warp threads, the periphery of said pulley constituting a movablesupport for portions of said warp threads and being interposed between asource of supply of said threads and the weaving and take-up mechanismof the loom, a pressure roll having trunnions in rolling contact withsaid guides, said rolls being rotatable by the threads and movable bygravitation toward the pulley, means for presenting the warp threads tothe periphery of the pressure roll, and means for yieldingly resistingthe rotation of the pulley.

4. A tension mechanism for looms, comprising hangers having basesaffixed to the frame of the loom, pulley bearings at their outerportions and guides inclined downwardly from the said bases toward thebearings, a pulley journaled in said bearings and free to be rotated bythe warp threads, the periphery of said pulley constituting a movablesupport for portions of said. warp threads and being interposed betweena source of supply of said threads and the weaving and take-up mechanismof the loom, a pressure roll having trunnions in rolling contact withsaid guides, said roll being rotatable by the threads and movable bygravitation toward the pulley, weights suspended. from said trunnionsand adapted to force the roll toward the pulley, means for presentingthe warp threads to the pe riphery of the pressure roll, and means foryieldingly resisting the rotation of the pulley.

A tension mechanism for looms, con1- prising hangers having basesallixed to the frame of the loom, pulley bearings at their outerportions and guides inclined downwardly from the said bases toward thebean ings, a pulley journaled in. said bearings and free to be rotatedby the warp threads, the periphery of said pulley constituting a movablesupport for portions of said warp threads and being interposed between asource of supply of said threads and the weaving and take-up mechanismof the loom, a pressure roll having trunnions in rolling contact withsaid guides, said roll being rotatable by the threads and movable bygravitation toward the pulley, means for yieldingly resisting therotation of said roll, means for presenting the warp threads to theperiphery of the pressure roll, and means for yieldingly resisting therotation of the pulley.

(3. A tension mechanism for looms, comprising hangers having basesafliXed to the frame of the loom, pulley bearings at their outerportions and guides inclined clownwardly from the said bases toward thebearings, a pulley journaled in said bearings and free to be rotated bythe warp threads, the periphery of said pulley constituting a movablesupport for portions of said warp threads and being interposed between asource of supply of said threads and the weaving and takeup mechanismOff the loom, a pressure roll having trunnions in rolling contact withsaid guides, said rolls being rotatable by the threads and movable bygravitation toward the pulley, means for presenting the warp threads tothe periphery of the pressure roll and weighted cords trictionallyengaged with the pulley to yieldingly resist its rotation.

7. A tension mechanism for looms, comprising hangers having basesafiixed to the frame of the loom, pulley bearings at their outerportions and guides inclined down wardly from the said bases toward thebearings, a pulley journaled in said bearings and free to be rotated bythe warp threads, the periphery of said pulley constituting a movablesupport for portions of said warp threads and being interposed between asource of supply of said threads and the weaving and take-up mechanismof the loom, a pressure roll having trunnions in rolling contact withsaid guides, said roll being rotatable by the threads and movable bygravitation toward the pulley, means for presenting the warp threads tothe periphery of the pressure roll, weighted cords frictionally engagedwith the pressure roll to yieldingly resist its rotation, and means foryieldingly resisting the rotation of the pulley.

In testimony whereof I have aflixed my signature, in presence of twowitnesses.

EDXVIN E. SIBLE Y.

lVitnesses:

C. F. Brown, P. W. PEZZETTI.

M Gopies of this patent may be obtained for five cents each, byaddressing the Commissioner of Patents,

Washington, D. C.

